Starch composition was determined enzymatically using the
Megazyme RS assay procedure (KRSTAR test kit, Megazyme Inter-national, County Wicklow, Ireland). Briefly, 100 mg of milled sam-ple were incubated in a shaking water bath with thermo-stable
pancreatica-amylase and AMG for 16 h at 37
C. During this in-cubation the non-resistant starch (non-RS) is solubilised and
hydrolysed to glucose by the two enzymes. The reaction was
terminated by the addition of equal volume of ethanol and the RS
was recovered as a pellet on centrifugation (3000 g) for 10 min. The
supernatants of this centrifugation and those of two consecutive
washings were removed by decantation and stored. RS pellets were
dissolved in 2 mol/L KOH and stirred for 20 min in an ice/water bath
over a magnetic stirrer. Sodium acetate buffer (1.2 mol/L, pH 3.8)
was added